Hi David,
Here is a simple example for adding a menu after the Help menu in Editor.
An important note is to put your load scripts into the /init folder within your custom folders. Any scripts in this folder load when Editor opens. You also need to use a menuloadhook to load the menu function.
function initMenus(){
menu_add -menu .Help "MyMenu";
menu_add .MyMenu. "MyCommand" -cmd {myFunction()}
}
add_hook("menuloadhook","initMenus");
Hope that helps!